高温高压进口下甲烷/氧气旋转爆震燃烧室增压特性与流场分析

Pressurization Characteristics and Flow Field Analysis of Methane/Oxygen Rotating Detonation Combustor at High Temperature and High Pressure Inlets

关键词:  旋转爆震燃烧室  理论分析  数值模拟  压力增益  推力

Key words:  Rotating detonation combustor  Theoretical analysis  Numerical simulation  Pressure gain  Thrust

摘要:

为建立旋转爆震增压比与发动机性能分析模型，推导了不同来流条件下旋转爆震燃烧室的增压比与推进性能，采用二维粘性非定常反应N-S方程对不同来流条件下的旋转爆震燃烧室流动特性进行数值模拟，获得高温高压来流条件下爆震波稳定传播与增压特性。理论分析表明，燃烧室的增压比由进口总温、燃烧室温升、波前反应物绝对马赫数确定，当进气压力给定时，单位推力也由这三个参数确定。数值模拟验证了理论分析推导的增压特性，得出高温高压来流条件下旋转爆震波起爆与稳定传播详细流场结构；在喷注压力一定时，爆震波波前绝对马赫数随进口总温升高而缓慢降低；燃烧室出口总温几乎恒定，即燃烧室增压比和推力性能主要受进口总温的影响。当进气总温提高时，燃料质量流量逐渐下降，爆震波强度下降显著，增压比和单位推力呈现对数下降趋势。

Abstract:

In order to establish an analysis model of rotating detonation pressurization ratio and engine performance， and analyze the pressurization ratio and propulsion performance of rotating detonation combustor under different flow conditions ，the flow characteristics of a rotating detonation combustor under different incoming flow conditions were simulated by using the Navier-Stokes equation of two-dimensional viscous unsteady reaction， and the stable propagation and pressurization characteristics of detonation wave under high incoming flow temperature and pressure were obtained.Theoretical analysis shows that the pressurization ratio of the combustor is determined by the total inlet temperature， the temperature rise of the combustor and the absolute Mach number of the wavefront reactants. When the inlet pressure is given， the unit thrust is also determined by these three parameters. Numerical simulation verifies the pressurization characteristics obtained from theoretical analysis， and obtains the detailed flow field structure of initiation and stable propagation of rotating detonation wave under high temperature and high pressure flow conditions. When the injection pressure is constant， the absolute Mach number in front of detonation wave decreases slowly with little change as the total inlet temperature rises， and the total outlet temperature of combustion chamber is almost constant， that is， the pressurization ratio and thrust performance of combustion chamber are mainly affected by the total inlet temperature. When the total inlet temperature increases， the fuel mass flow decreases gradually， the detonation wave intensity decreases significantly， and the pressurization ratio and unit thrust decrease logarithmically.